Stephen I is elected as the 23rd pope.
The primary problem facing Pope Stephen I is what to do about the "lapsed Christians" — Christians who gave in to pressure during the Decian persecution and renounced their faith, turned in other Christians, handed over scriptures to be burned, etc.
The strictest response, promoted by Novatian, is to force lapsed Christians to go through rebaptism as if they had never been Christians to begin with. The milder response is to insist that they repent, but upon penance offer them communion again.
Pope Stephen I favors the milder approach and his viewpoint will eventually become the accepted and orthodox one — namely, that no sin is so grave as to cause a person to cease being a Christian entirely. Novatian will be declared a heretic and Novtianism will be declared a heresy.